Joint Venture and Consortium Arrangements - Summarized Balance Sheet Information for Consolidated Joint Ventures (Detail) $ in Millions	Jun. 30, 2018 USD ($)	[1]
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Current assets	$ 74
Non-current assets	15
Total assets	89
Current liabilities	$ 81

[1] All balances at June 30, 2018 resulted from the Combination and are subject to change when additional information is obtained during the measurement period.